Exercise step



FIG. 1 is a perspective view of an exercise step showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is another perspective view thereof, showing the removable risers removed from the base of the exercise step;

FIG. 8 is a bottom plan view thereof; and,

FIG. 9 is another perspective view thereof, showing the removable risers partially removed from the base of the exercise step.

The broken lines in the figures illustrate portions of the exercise step that form no part of the claimed design. 

CLAIM The ornamental design for an exercise step, as shown and described. 